Writing instrument



FIG. 1 is a rear elevational view of a writing instrument showing a first embodiment of my new design;

FIG. 2 is a right side elevational view thereof, the left side being a mirror image thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a top plan view thereof; and

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a rear elevational view of a writing instrument showing a second embodiment of my new design;

FIG. 7 is a right side elevational view thereof, the left side being a mirror image thereof;

FIG. 8 is a front elevational view thereof;

FIG. 9 is a top plan view thereof; and,

FIG. 10 is a bottom plan view thereof. 

The ornamental design for a writing instrument, as shown and described. 